To be honest, that was my bad--I didn't bother checking it because I know it used to fail validation a month or so ago.

Looking at it now though

    [console.warn]

    https://www.ampproject.org/:22:42 The tag 'noscript > style : boilerplate - old variant' is deprecated - use 'noscript > style : boilerplate' instead. (see https://www.ampproject.org/docs/reference/spec.html#required-markup)

That 'warning' comes up as a whopping great big red error for my AMP pages that still have the old boilerplate. It seems AMP make an exception for their project site.